1. Field of the Invention
The present invention relates to an original feeding apparatus incorporated into an image forming system such as a copying machine, and more particularly it relates to an original feeding apparatus wherein an original set in a predetermined position is fed to a predetermined processing station and then is ejected out of the image forming system.
2. Related Background Art
In a conventional original feeding apparatus used with a copying machine and the like, until an operator has finished the treatment processes of his originals by using the original feeding apparatus, any other operators could not use the same original feeding apparatus. In fact, it is a practice that a number of persons must form a line to await for their turn for using the original feeding apparatus. However, it is apparent that such circumstances are very inefficient and time-consuming.
In view of the above, original feeding apparatuses wherein one of more "original groups" (each of which means a group of originals that are to be treated in the same copying condition) are previously set on an original support and the original groups are automatically and successively treated in accordance with the respective treating conditions requested for the respective original groups have been proposed. Such an apparatus is called as a "reserving type original feeding apparatus" and is constituted as shown in FIGS. 1 and 2. The construction shown in FIG. 1 is fully described in the Japanese Patent Laid-Open No. 62-65842 (corresponding to U.S. Ser. No. 905,935) and the construction shown in FIG. 2 is fully described in the Japanese Patent Laid-Open No. 62-222939 (corresponding to the U.S. Pat. No. 4,819,023 patented on Apr. 4, 1989).
In the original feeding apparatus shown in FIG. 1, a group of originals set on a tray 201 in an A portion (reserving portion) with the surface to be copied faced up are separated one by one from the bottom and the separated original is passed through paths (a). (b), (c), (d), (f), (i) and (j) and is fed to a tray 221 in a B portion (circulating portion). In the B portion, predetermined original reading processes are repeated a predetermined number of times through an original circulating movement (221.fwdarw.g.fwdarw.f.fwdarw.h.fwdarw.i.fwdarw.j.fwdarw.221.fwdarw.g.fwda rw.f.fwdarw.h.fwdarw.i.fwdarw.j.fwdarw.221 . . . ), and, after the processes have been completed, the original is moved from the tray 221 in the B portion through the paths (g), (f), (d), (b), (c) and (e) to an ejector tray 230 and is ejected thereon with the above-mentioned surface facing up. When the above-mentioned treatment regarding one original group has been completed, a similar treatment regarding the next original group situated on the tray 201 in the A portion is performed in the same manner. In this way, it is possible to continuously treat a plurality of original groups.
In the original feeding apparatus shown in FIG. 2, a group of originals set on a tray 301 in an A portion with the surface to be copied facing up are separated one by one from the bottom and the separated original is passed through paths (a), (b), (f), (h), (i), (j), (k), (l), (m), (h), (f), (h), (i) and (j) and is fed to a tray 321 in a B portion. In the B portion, predetermined original reading processes are repeated a predetermined number of times through an original circulating movement, and, after the processes have been completed, the original is moved from the tray 321 in the B portion through the paths (g), (f), (h), (i), (j), (k), (1), (m), (h), (f), (b) and (c) to an ejector tray 330 and is ejected thereon with the above-mentioned surface faced upside. When the above-mentioned treatment regarding one original group has been completed, as similar to FIG. 1, a similar treatment regarding the next original group situated on the tray 301 in the A portion is performed in the same manner. In this way, it is possible to continuously treat a plurality of original groups.
However, in the above-mentioned conventional original feeding apparatuses shown in both FIG. 1 and FIG. 2, since they each includes two trays one of which is the supply tray 201 or 301 in the A portion and the other of which is the ejector tray 230 or 330, the number of protruding portions projecting from the apparatus are increased, thus making the apparatus large. Further, since the ejector tray 230, 330 is disposed below the supply tray 201, 301, it was difficult to pick up or remove the ejected originals and to confirm the ejected original and/or the ejecting operation.
Further, in the example of FIG. 1, since the path in the A portion is complicated, if the original is jammed, the jam recovery treatment will be difficult. In addition, since the switch-back operation must be performed in the paths (b), (c) and (e) when the original is fed back from the B portion to the A portion, it takes a long time for feeding back the original from the tray 221 of the B portion.
On the other hand, in the example of FIG. 2, it is necessary that the originals must be turned over not to change the order of the originals when they are fed back from the B portion to the A portion through the paths (h), (i), (j), (k), (1), (m) and (h). Consequently, it takes a long time for feeding back the original.
Further, in the above-mentioned conventional original feeding apparatuses shown in both FIG. 1 and FIG. 2, as to a plurality of original groups, it is so designed that the original is fed from the supply tray 201 or 301 of the A portion to the tray 221 or 321 of the B portion and, after the original has been processed in the B portion, it is fed back to the ejector tray 230 or 330 of the A portion; whereas, as to the single original group, it is so designed that the original group is directly set in the tray 221 or 321 of the B portion and, after the original has been processed in the B portion, it is fed back to the tray 221 or 321 of the B portion. Accordingly, the construction regarding the plurality of original groups is independent from that regarding the single original group, and, therefore, the relation between the A portion and the B portion was not fully considered.
For example, the case where the originals are set on the tray 201 or 301 of the A portion during the treatment of one original group in the B portion was not considered. Further, in view of various combinations, there arises inconvenience in the feeding of the original from the A portion to the B portion and/or in the feeding of the original from the B portion to the ejector tray 230 or 330.
Furthermore, in the above-mentioned conventional apparatuses shown in both FIG. 1 and FIG. 2, if the sizes of the originals are different from each other, there will arise a problem that the original cannot be fed advantageously when the originals are fed from the reserving original supply portion (A portion) to the original circulating portion (B portion). That is to say, when all of the originals have the same size and lateral regulating guides in the A and B portions are adjusted to have a width corresponding to the size of the original, the originals are fed from the A portion to the B portion without trouble; but, if, during the treatment of the original in the B portion, the originals having different size are set in the A portion, problems will occur.
For example, it is assumed that the original group including the originals having B5 size are processed in the B portion.
The tray 221 or 321 of the B portion has lateral regulating guides for preventing the original from shifting in a direction perpendicular to an original feeding direction. Now, it is assumed that the originals having A4 size are set in the tray 201 or 301 of the A portion. In this case, when the original (A4 size) in the A portion is fed to the B portion after the treated original group in the B portion has been ejected onto the ejector tray, since the movement of the original is obstructed by the lateral regulating guides (set to have the B5 size width), the original will be jammed.
To the contrary, if the originals having A4 size are set in the B portion and the originals having B5 size are set in the A portion, the distance between the lateral regulating guides in the B portion will be wider than the width of the original fed from the A portion, with the result that there will arise a problem that the lateral regulating guides could not prevent the lateral movement of the original.